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Magnetic Resonance Imaging (MRI) of the Bones, Joints, and Soft Tissues

(MRI Scan of the Bones, Joints, and Soft Tissue)

Procedure Overview

What is magnetic resonance imaging (MRI)?

Magnetic resonance imaging (MRI) is a diagnostic exam that uses a combination of a large magnet, radiofrequencies and a computer to produce detailed images of organs and structures within the body. MRI does not use ionizing radiation, unlike X-rays or computed tomography (CT scans).

How does an MRI scan work?

The MRI machine is a large, cylindrical (tube-shaped) machine that creates a strong magnetic field around the patient and pulses of radio waves are sent from a scanner. The radio waves knock the nuclei of the atoms in your body out of their natural position. As the nuclei realign into proper position, they send out radio signals. These signals are received by a computer that analyzes and converts them to form a two-dimensional (2D) image of the part of the body being examined. This image then appears on a viewing monitor.

Some MRI machines look like narrow tunnels, while others are more spacious or wider. MRI scans can last from 30 minutes to two hours.

Reasons for the procedure

In orthopedics, an MRI may be used to examine bones, joints, and soft tissues such as cartilage, muscles, and tendons for injuries or the presence of structural abnormalities or certain other conditions, such as tumors, inflammatory disease, congenital abnormalities, osteonecrosis, bone marrow disease, and herniation or degeneration of discs of the spinal cord. MRI may be used to assess the results of corrective orthopedic procedures. Joint deterioration resulting from arthritis may be monitored by using magnetic resonance imaging.

There may be other reasons for your physician to recommend an MRI of the bones, joints, or soft tissue.

Risks of the procedure

Because radiation is not used, there is no risk of exposure to ionizing radiation during an MRI procedure. Each patient must be screened before exposure to the MRI magnetic field.

Due to the use of the strong magnet, special precautions must be taken to perform an MRI on patients with certain implanted devices such as pacemakers or cochlear implants. The MRI technologist will need some information regarding the implanted decide, such as the make and model number, to determine if it is safe for you to have an MRI. Patients who have internal metal objects, such as surgical clips, plates, screws or wire mesh, might not be eligible for an MRI exam.

If there is a possibility that you are claustrophobic then you should ask your physician to provide you with anti-anxiety medication that you can take prior to your MRI examination. You should plan to have someone drive you home afterwards.

If you are pregnant or suspect that you may be pregnant, you should notify your health care provider. To date there is no information indicating that MRI is harmful to an unborn child, however MRI testing during the first trimester is discouraged.

A doctor may order a contrast dye to be used during some MRI exams in order for the radiologist to better view internal tissues and blood vessels on the completed images.

If contrast is used, there is a risk for allergic reaction to the contrast. Patients who are allergic or sensitive to contrast dye or iodine should notify the radiologist or technologist.

If you have severe kidney disease or are on kidney dialysis, there is a risk of a condition called "nephrogenic systemic fibrosis" from the contrast dye. You should discuss this risk with your doctor prior to the test.

Nephrogenic Systemic Fibrosis (NSF) is a very rare but serious complication of MRI contrast use in patients with kidney disease or kidney failure.  If you have a history of kidney disease, kidney failure, kidney transplant, liver disease or are on dialysis, you must inform the MRI technologist or radiologist prior to receiving contrast.

MRI contrast may have an effect on other conditions, such as allergies, asthma, anemia, hypotension (low blood pressure), kidney disease, and sickle cell disease.

There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your doctor prior to the procedure.

Before the procedure

Your health care provider will explain the procedure to you and offer the opportunity to ask any questions you might have.

If your procedure involves the use of contrast dye, you may be asked to sign a consent form that gives permission to do the procedure. Read the form carefully and ask questions if something is not clear.

Prior to the examination you will be asked to change into a hospital gown. All personal items including body piercings, jewelry, clothing, purses and wallets must be removed an will be kept in a locker.

Notify the technologist if you have ever had a reaction to any contrast, or if you have other allergies, including medication and food allergies.

Generally, there is no special restriction on diet or activity prior to an MRI procedure.

Notify the technologist if you are pregnant or suspect you may be pregnant.

Before the examination, it is extremely important that you inform the technologist if any of the following apply to you:

  • You are claustrophobic and think you will be unable to lie still while inside the scanning machine. In this case you may be asked to reschedule your appointment. You may be suggested to contact your doctor to request a prescription for anti-anxiety medication that will help control your discomfort.

  • You have a pacemaker or have had heart valves replaced

  • You have any type of implantable pump, such as an insulin pump

  • You have metal plates, pins, metal implants, surgical staples, or aneurysm clips

  • You are pregnant or suspect you may be pregnant

  • You have any body piercing

  • You are wearing a medication patch

  • You are not able to lie down for 30 to 60 minutes

  • You have permanent eye liner or tattoos

  • You ever had a bullet wound

  • You have ever worked with metal (for example, a metal grinder or welder)

  • You have metallic fragments anywhere in the body

Based on your medical condition, your health care provider may require other specific preparation.

During the procedure

MRI may be performed on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your physician's practices.

Generally, MRI of the bones, joints, or soft tissue follows this process:

  1. You will be asked to remove any clothing, jewelry, eyeglasses, hearing aids, hairpins, removable dental work, or other objects that may interfere with the procedure.

  2. If you are asked to remove clothing, you will be given a gown to wear.

  3. If you are to have a procedure done with contrast, an intravenous (IV) line will be started in the hand or arm for injection of the contrast dye.

  4. You will lie on a scan table that slides into a large circular opening of the scanning machine. Pillows and straps may be used to prevent movement during the procedure.

  5. The technologist will be in another room where the scanner controls are located. However, you will be in constant sight of the technologist through a window. Speakers inside the scanner will enable the technologist to communicate with and hear you. You will have a call button so that you can let the technologist know if you have any problems during the procedure. The technologist will be watching you at all times and will be in constant communication.

  6. A surface coil may be placed over the area to be examined if it is a relatively small area, such as a joint.

  7. You will be given earplugs or a headset to wear to help block out the noise from the scanner. Some headsets may provide music for you to listen to.

  8. During the scanning process, a clicking noise will sound as the magnetic field is created and pulses of radio waves are sent from the scanner. This sound can be quite loud.

  9. It will be important for you to remain very still during the examination, as any movement could cause distortion and affect the quality of the scan.

  10. At intervals, you may be instructed to hold your breath, or to not breathe, for a few seconds, depending on the body part being examined. You will then be told when you can breathe. You should not have to hold your breath for longer than a few seconds.

  11. If contrast dye is used for your procedure, you may feel some effects when the dye is injected into the IV line. These effects include a flushing sensation or a feeling of coldness, a salty or metallic taste in the mouth, a brief headache, itching, or nausea and/or vomiting. These effects usually last for a few moments.

  12. You should notify the technologist if you feel any breathing difficulties, sweating, numbness, or heart palpitations.

  13. Once the scan has been completed, the table will slide out of the scanner and you will be assisted off the table.

  14. If an IV line was inserted for contrast administration, the line will be removed.

While the MRI procedure itself causes no pain, having to lie still for the length of the procedure might cause some discomfort or pain, particularly in the case of a recent injury or invasive procedure such as surgery. The technologist will use all possible comfort measures and complete the procedure as quickly as possible to minimize any discomfort or pain.

On occasion, some patients with metal fillings in their teeth may experience some slight tingling of the teeth during the procedure.

After the procedure

You should move slowly when getting up from the scanner table to avoid any dizziness or lightheadedness from lying flat for the length of the procedure.

If any sedatives were taken for the procedure, you may be required to rest until the sedatives have worn off. You will also need to avoid driving.

If contrast dye is used during your procedure, you may be monitored for a period of time for any side effects or reactions to the contrast dye, such as itching, swelling, rash, or difficulty breathing.

If you notice any pain, redness, and/or swelling at the IV site after you return home following your procedure, you should notify your physician as this could indicate an infection or other type of reaction.

Otherwise, there is no special type of care required after a MRI scan of the bones, joints, and soft tissues. You may resume your usual diet and activities, unless your physician advises you differently.

Your physician may give you additional or alternate instructions after the procedure, depending on your particular situation.

Online Resources

The content provided here is for informational purposes only, and was not designed to diagnose or treat a health problem or disease, or replace the professional medical advice you receive from your physician. Please consult your physician with any questions or concerns you may have regarding your condition.

This page contains links to other websites with information about this procedure and related health conditions. We hope you find these sites helpful, but please remember we do not control or endorse the information presented on these websites, nor do these sites endorse the information contained here.

American Academy of Orthopedic Surgeons

American Cancer Society

Arthritis Foundation

National Cancer Institute (NCI)

National Institute of Child Health and Human Development

National Institutes of Health (NIH)

National Library of Medicine

National Osteoporosis Foundation

Osteoporosis and Related Bone Diseases - National Resource Center - NIH

Radiological Society of North America

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